Seroatlas · Human Serome Atlas

PSG9

Pregnancy-specific beta-1-glycoprotein 9

Also known as: PSG11, PSG9_HUMAN, PSGII

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
Q00887
Gene
PSG9
Ensembl
ENSG00000183668
Chromosome
19
Canonical length
426 aa
Protein class
Plasma proteins, Predicted membrane proteins, Predicted secreted proteins
Secretome location
Secreted in female reproductive system

OverviewNCBI Gene

The protein encoded by this gene is a member of the pregnancy-specific glycoprotein (PSG) family. This protein family and the closely related carcinoembryonic antigen cell adhesion molecule (CEACAM) gene family are both members of the immunoglobulin superfamily, and are organized as a large gene cluster. This protein is thought to inhibit platelet-fibrinogen interactions. Several studies suggest that reduced serum concentrations of PSGs are associated with fetal growth restrictions, while up-regulation of this gene has been observed in colorectal cancers. Several pseudogenes of this gene are found on chromosome 19. Alternative splicing results in multiple transcript variants that encode multiple protein isoforms. [provided by RefSeq, Sep 2014]

Canonical amino-acid sequenceUniProt

426 residues, UniProt reviewed canonical sequence.

>Q00887|PSG9
     1  MGPLPAPSCT QRITWKGLLL TASLLNFWNP PTTAEVTIEA QPPKVSEGKD VLLLVHNLPQ
    61  NLPGYFWYKG EMTDLYHYII SYIVDGKIII YGPAYSGRET VYSNASLLIQ NVTRKDAGTY
   121  TLHIIKRGDE TREEIRHFTF TLYLETPKPY ISSSNLNPRE AMEAVRLICD PETLDASYLW
   181  WMNGQSLPVT HRLQLSKTNR TLYLFGVTKY IAGPYECEIR NPVSASRSDP VTLNLLPKLP
   241  IPYITINNLN PRENKDVLAF TCEPKSENYT YIWWLNGQSL PVSPGVKRPI ENRILILPSV
   301  TRNETGPYQC EIRDRYGGLR SNPVILNVLY GPDLPRIYPS FTYYRSGENL DLSCFTESNP
   361  PAEYFWTING KFQQSGQKLF IPQITRNHSG LYACSVHNSA TGKEISKSMT VKVSGPCHGD
   421  LTESQS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PSG9 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Secreted
Secreted
Yes
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.34
Highest tissue expression
100 nTPM

Expression across tissuesHPA

Tissue

  • placenta: 100 nTPM
  • smooth muscle: 0.7 nTPM
  • colon: 0.3 nTPM
  • parathyroid gland: 0.3 nTPM
  • spleen: 0.3 nTPM
  • bone marrow: 0.2 nTPM

Single-cell type

  • syncytiotrophoblasts: 329 nCPM
  • epididymal efferent duct absorptive cells: 13 nCPM
  • endometrial glandular cells: 11 nCPM
  • retinal bipolar cells: 9 nCPM
  • extravillous trophoblasts: 7 nCPM
  • adipocytes: 4.5 nCPM

Immune cell

  • eosinophil: 0.1 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • cerebellum: 1.8 nTPM
  • cerebral cortex: 1.2 nTPM
  • amygdala: 0.9 nTPM
  • white matter: 0.9 nTPM
  • basal ganglia: 0.8 nTPM
  • hippocampal formation: 0.8 nTPM

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
1.85
gnomAD pLI
0
gnomAD missense Z
-2.92
DepMap mean gene effect
0.09
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 2% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads PSG9 as an antibody target. Whether an autoantibody or antibody against PSG9 could matter depends on whether native PSG9 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

PSG9 is annotated as secreted, so native PSG9 circulates and is directly accessible to antibodies. Secreted and cell-surface proteins are the autoantibody targets most likely to act like drugs, blocking or depleting the native protein.

Annotation status

The present source text does not explicitly label PSG9 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/PSG9. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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